Clock and associated timekeeping mechanism



y 1- A. H. NEUREUTHER 2,248,411

CLOCK 'AND ASSOCIATED TIMEKEEPING MECHANISM Filed March 26, 1930 4 Sheets-Sheet 1 I INVENTR. l y I I I Jul 8, 1941. A. H. NEUREUTHER 2,248,411

CLOCK AND ASSOCIATED TIMEKEEPING MECHANISM Filed March 26, 1930 4 Sheets-Sheet 2 \3 as 2 a5 I 1 F166 24/ L J4 v 1 INVENTO I, I {/1 l I,

y 941. A. H. NEUREUTHER .1 2,248,411 CLOCK AND ASSOCIATED TIMEKEEPING MEQHANISM Filed March 26, 1950 Q 4 Sheets-Sheet 3 y 941. A. H. NEUREUTHER 2,248,411 CLOCK AND ASSOCIATED TIM-EKEEPING MECHANISM 1 Filed March 26, 1930 4 Sheets-Sheet 4 INVENTO Patented July 8, 1941 CLGCK AND ASSOCIATED TIMEKEEPING MECHANISM Andrew H. Neureuther, Peru, IIL, assignor, by

mesne assignments, to General Time Instruments Corporation, New York, N. Y., a corporation of Delaware Application March 26, 1930, Serial No. 439,040

16 Claims.

My invention relates to clocks and associated time keeping mechanisms and has for its object the production of means whereby the usual clocks of ordinary time keeping qualities can be controlled so that they will continuously keep accurate time in step with suitable electric currents such as are generally utilized for lighting and power purposes.

It is a well known fact that ordinary clocks such as employ springs or weights, which are either wound by hand, or by mechanical or electrical means, will not keep accurate time even with the highest grade of clock and watch escapements and even though the power spring is continually wound to produce a fixed amount of tension because temperature and lubrication etc. affeet the timing qualities of these escapements or time keeping means.

Further, in those types of clocks that utilize self starting synchronous motors directly geared to move the clock hands, the observer can never be certain of the correct time because in case of the stoppage of the current for any reason the hands are stopped and will start again when the current comes on and no time is recorded or indicated during the stoppage interval, Also in those types of clocks that utilize the non-self starting synchronous motors the hands are stopped when the current is interrupted and will remain stationary until the motor is again started by the hand of the operator.

I attain the above mentioned objects by continually controlling the movements of the escapement of the clock by means of engaging the reciprocating or moving part of said escapement with a similarly moving part of a synchronously actuated and controlled device associated with said clock mechanism. Said synchronously actuated and controlled device may be motivated by the usual alternating current or an interrupted direct current from a commercial lighting circuit, as well as the time signal broadcasting ether waves sent out by radio broadcasting stations. Should the motivating device be stopped for any reason for a given period such as a power line break down, the moving part of my synchronously actuated and controlling device is automatically so deposed that it will not interfere with the free action of the moving part of the escapement so that the clock mechanism will continue to function in its usual manner and thus continue keeping time during the power current interruption as accurately as its escapement construction is capable of performing. As soon as the power.

circuit is again established the moving part of the escapement is again controlled by the moving member of the motivated device, it being again automatically restored to its said controlling position.

I accomplish these above mentioned objects by means of the accompanying drawings which show a few forms of the application of my device to an ordinary clock having the usual marine escapement, in which drawings Fig. -1 is a front view of one application of my invention.

Fig. 2 is a top view of same.

Fig. 3 is a side view of same.

Fig. 4 is a front view of another embodiment of my invention.

Fig, 5 is a top view of said embodiment.

Fig. 6 is a side view of said embodiment.

Fig. 7 is a front view of another embodiment of my invention.

Fig. 8 is a partial sectionalview along a line [-2 of Figure 7.

Fig. 9 is a front view of another embodiment of my invention.

Fig. 10 is a side view of said embodiment showing the motor in partial sectional View along a line 3-4 of Fig. 9.

The same numerals represent the same parts throughout the several views.

In the drawings I represents a clock movement of the usual marine type having frame plates 2 and 3. Between plates 2 and 3 is pivotally mounted the balance wheel 4 which is mounted on a balance shaft 5. Balance wheel 4 carriesthe impulse pin 6 and the shaft 5 has the slot 1 which pin 6 and slot 1 cooperate with one end 8 of the lever 9 which lever is mounted on a shaft H] which is journaled in said plates 2 and 3 and which lever 9 carries the usual pallets H which engage the teeth of the escape wheel I2 which is mounted on a shaft l3 which is journaled in plates 2 and 3. Said shaft l3 has an enlarged part [4 and a still larger cylindrical part I5 which serves as a limitin or banking means for the projecting members l6 and [7' which are shown integrally formed in the other end of said lever 9. Projecting members [6 and I I each has its end formed with an angular approach as shown on the side adjacent to part [5 which will permit the end of member 18 to readily and positively enter the space between said projecting members l6 and I1 after said member l8 has been withdrawn by the stoppage of the electric current and again inserted when the electric current is restored as will be explained further along. Member I8 is preferably a resilient, or a resiliently mounted member having one end fastened to a lever i9 by means of a stud as shown. Lever l9 has a long slotted aperture 2| on one end adjacent to member l3 and a shorter slotted aperture 22 on its other end which is pivotally connected with another lever 23 by means of a pin 24 projecting into said slotted aperture 22. Said lever I9 is held against said pin 24 by means of a spring 25 one end of which spring is fastened to said lever 23 and the other end presses against the end of lever I9 as shown. Lever 23 is mounted on a shaft 25 which is suitably journaled in plates 2 and 3 and said lever further has an iron armature 2T fastened on its lower extremity whose position is controlled by means of the electro-magnet which has pole pieces 29 adjacent to said armature 21' and against which said armature is positioned (as shown in the solid lines) when said electro-magnet is energized. When said electro-magnet is de-energized the spring 39 one end of which is pivotally connected to lever 23 adjacent to armature 21, pulls said lever and armature away from the pole pieces 29 so that the lower end of lever 23 is against the stop pin 3|. It is evident that as the armature 21 moves from the pole pieces 29 to the stop pin 3| that the end of member l8 moves outwardly out of range of the projecting members l6 and I! of the lever 9 and that as said armature 21 moves from said stop pin 3| against the pole pieces 29 the end of member 18 move inwardly toward part l5 and between the projecting members l6 and H. The function of the slotted aperture 22 on lever 19 and the spring 25 on lever 23 is to form a yielding connection in case the end of member |8 should strike the end of projecting member IE or 17 it will enter without unduly straining any part of the associated parts. Moving in the long slotted aperture 2| is a pin 32 which is fastened on a disk 33 which is mounted on a shaft 34 which is journaled on a bracket 35 which is mounted on plate 2.

Shaft 34 is preferably rotated by means of a synchronous motor which synchronous motor may be either of the non-self starting or the self starting type which synchronous motor will rotate the disk 33 at one half of the proper speed required by the clock escapement to keep accur rate time on the hands of a clock for pin 32 will impart to said lever l9 a reciprocating motion thus movingthe free end of member |8 up and down into engagement with projecting members l6 and I! for each rotation of the disk 33 and shaft 34 thus causing the end of member |8 to reciprocate at the same rate per unit of time that the balance wheel rotates and the lever 9 reciprocates to keep correct time on the hands of the clock.

It is evident from the above description that if the synchronous motor is run from a commercial lighting or power current in which the number of the alternations of the alternating current flowing thereon is regulated and controlled to a given number per unit period of time that the member |8 will control and regulate the reciprocations of the lever and balance wheel so that they will only reciprocate the same number of times that the member l8 will and therefore unless the reciprocations of the lever 9 and balance wheel 4 of the clock movement are already in synchronism with said member 8 the said member |8 will interfere and completely control the movement of the said lever 9 and balance wheel 4 and thus keep the hands in accurate time relation synchronized with the alternations of the current supplied. Furthermore, since the electromagnet 28 is supplied with the current from the same circuit as that which supplies the synchronous motor it is evident that when the current is flowing in the power line, that the electromagnet 28 holds the member H3 in operative engagement with the projecting members l6 and l! of the escapement lever 9, and when the flow of current in the line is stopped for any reason the member |8 will be withdrawn from its operative connection with the projecting members l6 and I! and the clock movement itself will continue to function as usual and operate the hands in time keeping relation without the regulating influence of the synchronizing member l8. It is further evident that as soon as the current again starts to flow in the power line the member l8 will again be put into operative connection with the projecting members l6 and ll of the clock lever 9 and the hands controlled in accordance with the synchronizing current infiuencing means.

In case a usual non-self starting synchronous motor is used to operate my synchronizing influencing means, I find it advisable to use an external automatic starting means by having ratchet teeth 36 formed on disk 33 which is actuated by a pawl 31 which is journaled on said pin 24 and has a point 38 which engages said teeth 39 on beginning its forward motion (see dotted position in Figure 1) when the electromagnet 28 is energized when the current again starts flowing in the electrical line circuit. The point 33 is raised out of engagement with the teeth near the termination of said forward motion by means of cam 39 passing over a pin 40 fastened to said bracket 35. It is evident that the means above described will automatically bring the rotor of the non-self starting synchronous motor into step so that the rotor will continue to run in synchronous rotation. It is evident that in using a self starting synchronous motor it will not be necessary to use the teeth 35 or the pawl 31 etc. comprising the means for automatically starting the rotor of same.

As the clock movement remains in constant operation in my invention I prefer to employ the following means to keep the main spring of same wound sufficiently to assure 24 hours continued operation after the electric current is stopped. The barrel 4| contains the driving spring 42 one end of which spring is secured in said barrel and the other end of said spring is secured to the winding arbor 43 in the usual manner. Mounted on the winding arbor 43 is a worm wheel 44 which meshes with a worm 45 mounted on a shaft 45 which is journaled in the bearings 41 on a frame associated with the movement plates 2 and 3. Fastened on shaft 46 is a ratchet wheel 48 which has a lever 49 journaled on said shaft 45 and placed between said ratchet wheel 48 and the left hand bearing 41 as shown in Figure 1, Lever49 has a pin 50 mounted on it which projects into a suitable cam 5| fastened on a shaft 52 journaled in the bracket 35. Mounted on said shaft 52 is a large driving gear 53 which is driven by means of a pinion 54mounted on said shaft 34 which shaft 34 is driven by the synchronous motor as previously mentioned so that both the synchronizing relating means for the escapement and spring winding means are driven by the same motor. Lever 49 has a ratchet pawl 82 mounted on the pin 6| which is fastened on lever 49 and the power is wound tightly. that a usual suitable ratchet with pawl and winding keycan be attached on the worm wheel 44 held in engagement with teeth'of ratchet wheel 48 by means of the spring 63. The motion of 'lever 49 thus rotates ratchet wheel 48 which is held against reverse rotation by means of the pawl 64 mounted as shown (see Fig. 6). To-prevent the power spring from over winding or the spring winding means from interfering with the rotation of or stalling the synchronous motor, I employ a safety means on the lever in that I pivotally mount the upper part of said lever-49 by means of a pin 55 with the lower part of said lever 49 and then hold the two parts of said lever in alignment by mean of a suitable leaf spring 56 the lower end of which is rigidly fastened to the lower part of said lever 49 by means of the pins shown and the upper part of said spring 56 is slidably mounted to the upper part of said lever by means of said spring 55 passing between two pins fastened in the upper part of said lever 48 all of which is shown in Figure 3. It

is evident that the upper end of the lever 49 can move if the lower part is stationary because It is also evident and the winding arbor as to permit winding the power spring by hand should same be desired.

In the embodiment of my invention shown in Figures l, 5, and 6 I simplify the construction considerably by eliminating the electro-magnet 23, its armature 2i and the lever 23 which is pivotally mounted by means of the shaft 2%.

I accomplish this by employing means for keeping the end of resilient lever I8I which is attached to lever iQI centrally disposed in rela- 1 tion to the projections I5 and I! of escapement lever B. In order to do this I fasten said lever [9| to the shaft B ll and journally mount said shaft MI in an extension bracket from the movement plate as shown and further change said 1 lever I9! into abell crank lever by adding a projecting member downwardly at right angles to the horizontally disposed lever IQI then adjustably mount on said downwardly projecting part by means of the screw 59 the weight 58 so that the lever IQI and its resilient member IIlI will always come to rest in the horizontal position. Thus will the end of resilient member IBI be centrally disposedto the projections I6 and I! as above mentioned and as is shown in Figure l Whenever the synchronous motor stops because the current is stopped. This weight arrangement assisted by means of weight 60 on the gear 65 which is mounted on the shaft 34, which weight 60 is located .on line at right angles to a line passing through the center of the shaft 34 and the center of the pin 32 as shown in Figure 4 will thus always bring its associated resilient lever IGI in its centrally disposed position with reference to the banking part so that the escapement lever 9 will always be free to continue its reciprocations by virtue of the clock power driven means and not be controlled by said resilient member iSI touching its projections I6 and I! as said points are controlled when the synchronous motor is running. It is evident that when the current stoppage occurs the armature of the synchronous motor will not oifer resistance against rotation and therefore will be readily responsive to the action of the weights G0 and 58 to bring the member I8I into its horiz ontally disposed position and relation shown in Figure 4.

In the embodiment ,of my invention shown in Figures '7 and 8, I have entirely eliminated the 7 use of the auxiliary electromagnet 28 and the weighted system using the weights 58 and 60 above described. I accomplish this by pivotally mounting the lever I82 on the stud 20 on lever I92 as shown and then giving the actuating end of said lever I82 a sidewise or lateral motion bringing it into and out of the line of engagement with the projections-I6 and ll of the escapement lever 8. This sidewise or lateral motion is imparted to lever I82 by means of a slot IS in the otherend of lever I82 adjacent to its pivoting point in which slot a circular disk 6% mounted on the rotor shaft 61 is engaged so that any sidewise or lateral movement of the rotor is directly transmitted to said lever I82. The rotor 68 is so positioned in relation to its magnetic field-induced in its field winding 69 by the commercial lighting current that when said current is flowing, the rotor is drawn into the intense part of the magnetic field forcing its shaft end against the ball 10 and pressing the spring II thereby bringing said lever I82 in the operative position shown in solid lines in Figure 8 in which position the end of lever I82 engages the projections I6 and I! of escapement lever 9. When the flow of said current is stopped, deenergizing the magnetic field, it is evident that the spring II will instantly push the rotor out of the above mentioned intense magnetic position in said field and thus bring the end of the lever I82 out of engagement with the projections I6 and I! as shown in the dotted lines in Figure 8. In order to simplify this embodiment of my invention I use the pin 242 somewhat enlarged with a head 12 to retain lever I592 and further having an aperture I5 in same through which the rotor shaft &1 passes and may be journaled all as shown. The pressure exerted by the spring II is adjusted by means of the threaded screw '13 as shown. The rotor shaft 6'! communicates its rotation to the gear 65 which rotates the crank plate 33 by means of the pinion 14 mounted on said rotor shaft 61.

In the embodiment of my invention shown in Figures 9 and 10, I have entirely eliminated the use of the auxiliary electromagnet 28, the weighted system using the weights 53 and 60 and the system just previously described using the reciprocating lever I92 and the sidewise pivoted resilient lever I82 associated with said lever I92. I accomplish this by putting suitably shaped resilient members "I"! and 18 on projections I6 and ll of the escapement lever 9. I have shown members I6 and I! as being straight but it is evident that they may be formed with projecting parts to limit the contact of each with the surface of the cam shaped member IQ. Positioned between said resilient members I1 and I8 is a shaft 34 which is rotatably and slidably journaled in the movement frame and has mounted on its right hand end the gear Iii: all as shown (see Figure Q). Mounted on the end of said shaft 34 and located between said projections I! and I8 is projecting cam shaped member I9 having parts and iii substantially parallel to the shaft 34 and an inclined part 82 connecting said parallel parts 88 and 8t. It is evident from theconstruction shown when the current is operating the synchronous motor 69 and the rotor is pulled into the motor field as described below, and the parallel part 80 of cam T9 lies in the plane of the projecting resilient members '11 and I8 of the escapement lever '9 as shown in the dotted'lines in Fig. 10, that the reciprocations of said escapement lever 9 will be controlled by the iii.

rotations of said shaft 34 and when the cam '19 is moved along (which occurs when the current stops flowing in the circuit) so that the parallel surface Si lies in the plane of said resilient members ii and 78, as shown in the solid lines in Figure 10, the escapement lever 9 is entirely controlled by the balance wheel 4 which is driven by the time movement as previously above mentioned. The gear 65 is operated by a shrouded pinion M having the shrouded sides 83 as shown which pinion is mounted on the rotor shaft 61 of the synchronous motor 89. It is evident from the said connections that any sidewise motion of the rotor shaft 61' is communicated to the gear 65 and the cam 19 as above described. It is evident that with a properly speeded synchronous motor that the cam 19 could be mounted directly on the rotor shaft 81 omitting the shaft 34 and the gear 65. It is also evident that the cam 19, instead of being rigid as shown can be made of a suitably shaped resilient member in which case the members I! and 18 on lever 9 could be somewhat less resilient. In Figure 10 an adjustable sleeve 84 having the external and internal screw threads shown is used to limit the position of the ball it to completely control the sidewise motion of the rotor shaft 61. Said sleeve 84 is locked in position by means of the nut 85 shown.

From the above description it is evident that I have produced an extremely simple, efiective and inexpensive means for synchronously controlling and regulating the movements of the escapement means of ordinary low priced clocks utilizing in accomplishing the same among the other means mentioned in the embodiments submitted the impulse of the alternating current of the commercial lighting systems. It is further evident that I have similarly produced an extremely simple, effective and inexpensive means for keeping the power driving means of an ordinary clock continuously wound to keep its escapement lever in continuous operation. The combination of these above mentioned devices with an ordinary low priced clock movement it is evident makes such a clock an extremely accurate and continuously operated time piece, extremely imple and inexpensive to produce.

It will be understood of course, that while I have here shown a few of the embodiments of :y invention that I do not wish to limit myself to the forms shown but desire to have these taken as illustrative of any or all the forms that come fairly within the scope of the appended claims.

I claim:

1. In combination, an escapement comprising a pallet fork co-acting with a balance wheel and a hair spring having a standard time rate, power driving means to continuously operate said escapement, a time indicating means continuously actuated and rated by the movement of said escapement, a synchronous motor actuated by the alternating current from a commercial lighting system, movement transmitting means attached to and actuated by said motor and means on said pallet fork for directly co-acting with said movement transmitting means to control the movements of the pallet fork independently of the standard time rate of the balance wheel and hairspring as long as said current flows.

2. In combination, an escapement comprising a pallet fork co-acting with a balance wheel and a hair spring having a standard time rate, power driving means to continuously operate said escapement, a time indicating means continuously actuated and rated by the movement of said escapement, a self-starting synchronous motor actuated by the alternating current from a commercial lighting system, movement transmitting means attached to and actuated by said motor and means on said pallet fork for directly coacting with said movement transmitting means to control the movements of the pallet fork independently of the standard time rate of the balance wheel and hairspring as long as said current flows.

3. In combination, an escapement comprising an escape wheel actuating a pallet fork co-acting with a balance wheel and a hair spring having a standard time rate, power driving means to continuously operate said escape Wheel, a time indicating means continuously actuated and rated by the movement of said escapement, a synchronous motor actuated by the alternating current from a commercial lighting system, movement transmitting means attached to and actuated by said motor and means on the pallet fork for directly co-acting with said movement transmitting means to control the movement of said escapement independently of the standard time rate of the balance wheel and hair spring as long as said current flows.

4. In combination, an escapement comprising an escape wheel actuating a pallet fork co-acting with a balance wheel and a hair spring having a standard time rate, power driving means to continuously operate said escape wheel, a time indicating means continuously actuated and rated by the movement of said escapement, a selfstarting synchronous motor actuated by the alternating current from a commercial lighting system, movement transmitting means attached to and actuated by said motor and means on the pallet fork for directly co-acting with said movement transmitting means to control the movement of said escapement independently of the standard time rate of the balance wheel and hair spring as long as said current flows.

5. In a clock, an escapement having a standard time rate and a power driving means to actuate said escapement, in combination with electrical synchronous motion producing means, transmission mechanism connected with and actuated by said motion producing means, magnetic means bringing said mechanism into operative position, with means on a member of said escapement co-acting directly with said mechanism thereby controlling the movement of said escapement independently of the standard time rate thereof, and means for removing said transmission mechanism from oo-acting with the member on said escapement when the means for producing synchronous motion is not actuated.

6. In a clock movement, a pallet fork and a power driving spring to actuate said pallet fork, in combination with electrical means for producing synchronous motion, transmitting mechanism continuously connected therewith for directly co-acting with said pallet fork to control the movements thereof when said means for producing synchronous motion is actuated and means for positioning said transmitting mechanism from directly co-acting with said pallet fork when said means for producing synchronous motion is not actuated.

7. In a clock, a timing means comprising an escapement wheel, a pallet fork, a standard rated balance wheel and hairspring, a power driving means to actuate said escapement wheel in combinaticn with electrical means for producing synchronous motion, transmitting mechanism continuously connected therewith for directly coacting with said pallet fork to control the movements thereof independently of the standard rated balance wheel and hairspring when said means for producing synchronous motion is actuated and means for positioning said transmitting mechanism from controlling the movements of said pallet fork when said means for producing synchronous motion is not actuated.

8. In a clock, a timing means comprising an escapement wheel, a pallet fork, a standard rated balance wheel and hairspring, a power driving means to actuate said escapement wheel in combination with a synchronous motor actuated from the alternating current from a commercial lighting line, intermediate transmitting mechanism continuously connected therewith for directly co-acting with said pallet fork to control the movements thereof independently of the standard rated balance wheel and hairspring as long as said alternating current flows and means for removing said transmitting mechanism from thus co-acting with said pallet fork when said current flow is interrupted.

9. In a clock, a timing means comprising an escapement wheel, a pallet fork, a standard rated balance wheel and hairspring, a power driving means to actuate said escapement wheel in combination with a self-starting synchronous motor actuated by the alternating current from a commercial lighting system, transmitting mechanism continuously connected therewith for directly coacting with said pallet fork to control the movements thereof independently of the standard rated balance wheel and hairspring as long as said current flows and means for removing said transmitting mechanism from thus co-acting with said pallet fork when said current flow is interrupted.

10. A clock, comprising a time indicating means, an escapement wheel, a pallet fork, a rated balance wheel and hairspring, a power driving means to actuate said escapement wheel in combination with a self-starting synchronous motor having a slidably mounted armature operated from the alternating current of a commercial lighting system, transmitting mechanism actuated by said armature directly co-acting with said pallet fork to control the movements thereof when said current flows and means for removing said transmitting mechanism from co-acting with said pallet fork when said current flow is interrupted.

11. In combination, an escapement comprising a pallet fork co-acting with a balance wheel and a hair spring having a standard time rate, power driving means to continuously operate said escapement, a time indicating means continuously actuated by the movement of said escapement, a synchronous motor actuated by the alternating current from a commercial lighting system, movement transmitting means on said motor and means on a member of said escapement for directly co-acting with said movement transmitting means on said motor whereby the movement of said escapement registers with said movement transmitting means independently of the standard time rat of the balance Wheel and hair spring as long as said current flows.

12. In combination, an escapement comprising a pallet fork co-acting with a balance wheel and a hair spring having a standard time rate, power driving means to continuously operate said escapement, a time indicating means continuously actuated by the movement of said escapement, a self-starting synchronous motor actuated by the alternating current from a commercial lighting system, movement transmitting means on said motor and means on a member of said escapement for directly co-acting with said movement transmitting means On said motor whereby the movement of said escapement registers with said movement transmitting means independently of the standard time rate of the balance wheel and hair spring as long as said current flows.

13. In a clock, an escapement having a standard time rate, a power driving means to actuate said escapement, a synchronous motor actuated by the alternating current from a commercial lighting system, movement transmitting means connected to and positively actuated in all of its movements by said motor, and means on a member of said escapement co-operating with said transmitting means to either retard or accelerate said escapement member in each direction of osciilation of said member.

14, In a clock, an escapement having a standard time rate, a power driving means to actuate said escapement, electrical synchronous motion producing means, an oscillating element conneoted to and positively actuated in each direction of oscillation by said motion producing means, and means on a member of said escapement directly co-acting with said oscillating element to either retard or accelerate said escapement member in each direction of oscillation of said member.

15. In a clock, an escapement having a standard time rate includin the following members, a balance wheel, a hair spring and a pallet fork in combination with a power driving means to actuate said escapement, a synchronous motor operated by the alternating current from a commercial lighting system, an oscillating element actuated by said motor, and means on said pallet fork co-acting with said element to either retard or accelerate said escapement member in each direction of oscillation of said member thereby keeping the movements of said escapement continuously in step with the alternations of said current.

16. In a clock system, a clock train having a time measuring element maintained in operation thereby, electromagnetic motion producing means, vibrating means governed by said motion producing means independent of the natural period of said element to keep said element operating in timed relation to the operation of said motion producing means, and electromagnetic means separate and distinct from said motion producin means energized by said current to maintain said element and said vibrating means in operative relationship and released automatically upon a failure of current to said motion producing means to relieve said element from the control of said vibrating means.

ANDREW H. NEUREUTHER. 

